Keto Boston Cream Pie

Step by Step Instructions

1. 1

   Prepare the cake pans

   Spray two 8-inch round cake pans with cooking oil and line the bottom with a parchment circle. Preheat the oven to 350 degrees F.

   
2. 2

   Special keto flour blend

   In a medium bowl, sift together almond flour, oat fiber, egg white protein powder, baking powder, xanthan gum, arrowroot powder, and salt. Set the bowl aside.

   For this step

   • 2 cups almond flour
   • 2/3 cup oat fiber
   • 1/3 cup egg white protein powder
   • 2 tablespoons baking powder
   • 1 tablespoon xanthan gum
   • 1 tablespoon arrowroot powder
   • 1/2 teaspoon salt
   
3. 3

   Mix wet ingredients

   In a large bowl, cream together 1/2 cup butter, oil and 1 ¾ cups granulated allulose using an electric mixer at medium speed. Mix until light and fluffy for about 3-4 minutes. Mix in eggs one at a time. Then mix in 2 teaspoons vanilla extract.

   For this step

   • 1/2 cup unsalted butter, softened to room temperature
   • 1/2 cup olive oil
   • 1 ¾ cups granulated allulose
   • 4 large eggs
   • 2 teaspoons vanilla extract
   
4. 4

   Finish cake batter

   Using a spatula, pour in about ¼ of the milk to the butter mixture. Mix until combined. Then sprinkle in ¼ of the dry ingredients and mix until combined. Continue alternating between adding each and mixing until just combined. 

   For this step

   • 1 ¼ cup milk of choice (I used macadamia nut milk)
   
5. 5

   Bake the cakes

   Evenly divide the cake batter between the two prepared cake pans. Bake at 350 degrees F for 28-30 minutes or until a toothpick inserted into the middle comes out clean. Remove the pans from the oven and set aside to cool for 3-4 minutes. Loosen the sides of the cake with a knife and then flip onto a wire rack to cool completely.

   
6. 6

   Make the custard

   In a medium saucepan, whisk together egg yolks and sugar until well combined. Whisk in cornstarch and salt. In a slow, steady stream, whisk in milk and then the cream. Add butter. Cook mixture over medium-low heat, stirring constantly with a wooden spoon, just until it starts to thicken. Immediately whisk mixture until smooth, then continue to cook and stir custard until it has come to a very low boil for 2 minutes, about 6 to 8 minutes total. Stir in vanilla. Cover with plastic wrap, pressing the plastic directly onto the surface. Chill for at least 3 hours and up to 24 hours.

   For this step

   • 6 large egg yolks
   • 1 cup granulated allulose
   • 1/4 cup cornstarch
   • pinch of salt
   • 2 cups milk of choice
   • 1/2 cup heavy cream
   • 2 tablespoons unsalted butter, softened
   • 2 teaspoon vanilla extract
   
7. 7

   Make chocolate ganache

   In a small bowl, combine powdered allulose and cocoa powder. Stir in hot water, butter and vanilla. Mix until combined. If frosting is too thick, add another ½ tablespoon of hot water until desired consistency is reached.

   For this step

   • 1 ⅓ cup powdered allulose
   • 3 tablespoons unsweetened cocoa powder
   • 3 tablespoons hot water
   • 1 teaspoon unsalted butter, softened
   • 1 teaspoon vanilla extract
   
8. 8

   Assemble

   To assemble, pile on the custard filling to one cake layer and spread around evenly, then top with second layer. Add the chocolate frosting on top of the cake and either spread it to the edges or you can let it spill over a bit.